Abstracts of the Academy of Dental Materials Annual ... - IsiRed

More documents

Recommendations

Info

all three oxide ceramics (28.4 ± 3.3 MPa to 32.7 ± 3.4 MPa) was significantly higher (p ≤ 0.05) than to the non-coated groups AS and APA (9.0 ± 1.8 MPa to 19.6 ± 2.2 MPa). In contrast to some of the AS and APA groups thermocycling had no significant effect (p ≤ 0.05) on resin-bond strength to the coated groups. Conclusions: The bond strength of self-adhesive resin cement containing 4-META to Y-TZP, Al2O3 and In-Ceram Zirconia ceramics can be improved by the surface functionalization of oxide ceramics with a nano-structured alumina coating. Furthermore, bond strength to coated oxide ceramic surfaces is resistant to degradation by thermocycling. doi:10.1016/j.dental.2010.08.119 112 Effect of tooth preparation on the fit of Y-TZP copings R.I. Hmaidouch, P.E. Neumann, W.-D. Mueller “Charité” Universitaetsmedizin Berlin, CC3 Dental School, Berlin, Germany Objectives: This study evaluated marginal and internal adaptation of Cerec3 copings using two occlusal preparation forms. Materials and methods: Two metal master models (tooth 36: A, normal occlusal reduction; B, flat occlusal reduction) were used. 80 gypsum dies were produced from each master model. 16 groups were established by combining the two preparation forms with two luting space settings/ LSS (100 and 50 �m) and four cements (zinc phosphate/ZPC, Panavia21/p21, experimental cement.1/Exp.1 and Exp.2). 80 copings were milled using Y-TZP 1 ceramic, 5 pieces for each group. Copings were cemented, embedded and then sectioned bucco-lingually and mesio-distally. Marginal gaps (MG) and internal gaps (IG) were measured using a light microscope at 40×, 82 measurements for each coping. Results: One-way ANOVA (P < 0.05) showed significant difference between copings with normal occlusal form and copings with flat occlusal form, between copings with LSS of 100 �m and those with LSS of 50 �m. Also between copings cemented with P21 and the other cements. Results are summarized in Table 1: Preparation form CementLSS 100 �m LSS 50 �m MG IG MG IG A ZPC 81.69 ± 2.55 120.46 ± 8.60 110.31 ± 7.22 131.68 ± 18.16 P21 73.63 ± 6.81 112.39 ± 4.23 85.69 ± 4.88 96.09 ± 4.27 Exp.1 76.19 ± 9.12 121.43 ± 10.17 94.78 ± 14.63 122.43 ± 13.11 Exp.2 74.73 ± 7.06 130.30 ± 6.04 103.91 ± 8.12 132.12 ± 9.28 B ZPC 44.59 ± 7.09 113.12 ± 2.48 71.26 ± 3.34 87.67 ± 10.20 P21 31.57 ± 9.16 102.87 ± 1.96 61.54 ± 5.97 71.42 ± 4.29 Exp.1 50.73 ± 19.94 109.16 ± 6.88 81.04 ± 9.42 106.06 ± 2.59 Exp.2 49.87 ± 8.85 117.22 ± 7.98 68.64 ± 15.14 104.84 ± 11.03 1 Vita YZ-20. dental materials 26S (2010) e1–e84 e53 Conclusions: Fit of copings with flat occlusal form was better than those with normal occlusal form, copings milled with 100 �m LSS fitted better than those milled with 50 �m LSS. Fit of copings cemented with P21 was better than those cemented with the other cements. doi:10.1016/j.dental.2010.08.120 113 Evaluation of newly developed experimental zirconia primer S. Hotta, A. Arita, T. Kumagai, T. Sakuma GC, Corp., Tokyo, Japan Objectives: Zirconia ceramics are of current interest because of metallic, allergy-free, recent improvement of the CAD/CAM system, and aesthetic requirement. The aim of this study was to evaluate the bond strength of newly developed experimental zirconia primer and various commercially available zirconia primers. Materials and methods: Zirconia block (GC Aadva Zr) was polished with SiC paper (#1500) or sandblasted by alumina (50 �m). Tested primers were MSZ007 (GC), Clearfil ceramic primer (Kuraray), AZ primer (Shofu), Metal/Zirconia primer (Ivoclar Vivadent), Monobond plus (Ivoclar Vivadent), and Z- PRIME PLUS (BISCO). The zirconia surface was treated with each primer according to the manufactures instructions, then delimited by masking tape with a hole of 3.0 mm in diameter, and bonded to a stainless rod using LINKMAX (GC). In addition, we evaluated some company’s primers using the same company’s resin cement and self-adhesive resin cements, SA cement (Kuraray), Maxcem Elite (Kerr), and Unicem capsule (3M ESPE). These bonded specimens were immersed in water at 37 ◦ C for 24 h and then subjected to tensile bond strength (TBS) testing with a crosshead speed of 1 mm/min. Results: TBSs including standard deviations were shown as follows (n = 5): Primer/LINKMAX TBS/MPa (SD)/#1500 TBS/MPa(SD)/ Sandblasted MSZ007 45.4(9.3) 40.6(8.4) Clearfil ceramic primer 43.8(8.3) 45.6(9.0) AZ primer 45.5(5.7) 44.5(13.9) Metal/Zirconia primer 39.2(6.4) 35.3(12.9) Monobond plus 46.2(4.5) 36.5(9.8) Z-PRIME PLUS 37.0(10.3) 47.9(8.0)
e54 dental materials 26S (2010) e1–e84 Primer Cement TBS/MPa Clearfil ceramic primer Clearfil esthetic cement (SD)/#1500 TBS/MPa(SD)/ Sandblasted 36.0(10.9) 28.6(13.1) AZ primer Resicem 37.5(3.7) 36.7(3.9) Metal/Zirconia Multilink 26.4(5.4) 30.7(10.1) primer automix No primer SA cement 28.4(13.5) 38.1(3.7) No primer Maxcem elite 38.7(10.7) 43.0(11.3) No primer Unicem capsule 34.9(4.7) 27.8(8.8) Conclusions: Tensile bond strength of newly developed MSZ007 performed as well as other zirconia primers currently available in the market at 1 day. Tensile bond strength depends on the resin cement used. This study suggests that it is important to use the same resin cement to evaluate the bonding performance of the primer. doi:10.1016/j.dental.2010.08.121 114 Effect of light on the micro-mechanical properties of dualcured self-adhesive resin cements N. Ilie, A. Simon Ludwig-Maximilians-University, Munich, Germany Objectives: To analyze the effect of light on the micro-mechanical properties of 8 popular dual-cured self-adhesive resin cements (G-Cem, RelyX Unicem, G- Cem Automix, Max-cem Elite, Breeze, SmartCem2, i-CEM, Clearfil SA) by comparing them with two conventional dual-cured resin cements (Dentin Build and Multilink Automix). Materials and methods: For each material, four different curing procedures were applied. The cements were cured for 20 s with an LED curing unit (Freelight 2) by applying the unit directly on the samples’ surface, at a distance of 5 mm and 10 mm. Additionally, no light was allowed to reach the samples in order to determine the effect of the chemical curing only. Twenty minutes after curing, the samples were stored for one week at 37 ◦ C in a water saturated atmosphere. The micro-mechanical properties – Vickers hardness, modulus of elasticity, creep and elastic/plastic deformation – were analysed. Results: A very strong influence of the material as well as filler’s volume and weight on the micro-mechanical properties was measured, whereas the influence of the amount of light and type of cement – conventional or self-adhesive – was generally low. The influence of light on the polymerization process was material dependent, with four different behaviour patterns to be distinguished. 1. Less sensitivity to the way of cure, be it dual-cured with different light intensities or only chemical cured (Dentin Build, Breeze). 2. Significant differences only between dual-curing and chemical-curing, whether the amount of light was not a significant factor of influence (max-cem Elite, i-CEM, Clearfil SA). 3. Significant differences not only between dual-curing and chemical-curing, but also between the different amount of light (RelyX Unicem, Multilink Automix, G-Cem). 4. Decrease of properties with decreased light amount but no differences between chemical curing and dual-curing with lower intensity (G-Cem automix, SmartCem2). Significant higher micro-mechanical properties were measured for the conventional resin cements compared to the self-adhesive cements, although this difference was low. Within the self-adhesive resin cements group, the variation in micro-mechanical properties was high (Tukey’s HSD test, ˛ = 0.05). Conclusions: The selection of the suitable resin cements should be done besides its adhesive properties also by considering its micro-mechanical properties and curing behaviour. doi:10.1016/j.dental.2010.08.122 115 Effect of silane heat treatment on resin-cement and glassceramic adhesion F.P.P. Leite 1 , R.F. Carvalho 1 , F.L.G. Cruz 1 , Memn Martins 1 , J.R.C. Queiroz 2 , A.D. Vanderlei 2 , M. Ozcan 3 1 Universidade Federal De Juiz De Fora, Brazil 2 Universidade Estadual Paulista, Brazil 3 Zurich University, China Objectives: The following hypothesis was tested: silane heat treatment improves the bond strength of resin cement to glass ceramic. Materials and methods: 24 Ceramic blocks (Vita VM7, VITA) (6 mm × 6mm× 8 mm) were obtained. The cementation surface of each block was duplicated in resin-composite (W3D Master, Wilcos). Ceramic blocks were randomly assigned into 3 groups (n = 6/per group): G1: etching with 10% HF (Dentsply) for 20 s + rinsing with water for 60s+drying (control); G2: 10% HF for 20 s + rinsing with water for 60s+drying + silane then dried in a furnace at 100 ◦ C for 2 min (F-1800-EDG, São Paulo, Brazil); G3: silane then dried in a furnace at 100 ◦ C for 2 min (F-1800- EDG, São Paulo, Brazil). The ceramic blocks were cemented to the composite blocks using a resin cement (Panavia F, Kuraray). The cemented blocks were sectioned with a diamond disk under coolant irrigation to obtain microbars with 0.8 mm 2 of bonding area. Each bar was attached to an adapted device and the microtensile test was performed. Results: Silane heat treatment media resulted in significant differences among the groups (P < 0.05) (One-way ANOVA and Tukey test, ˛ = 0.05). The mean bond strengths (MPa) were as follows: G1: 17.63 ± 2.30a; G2: 19.01 ± 3.19a; G3: 9.13 ± 2.76b.
Page 1 and 2:
materials dental dental materials d
Page 3 and 4:
Volume 26 Supplement 1 2010 ISSN 01
Page 5 and 6:
e26 57. Effect of cavity configurat
Page 7 and 8:
e58 125. Adhesion between zirconia
Page 9 and 10:
© 2010 by the Academy of Dental Ma
Page 11 and 12: e2 dental materials 26S (2010) e1-e
Page 19 and 20: e10 dental materials 26S (2010) e1-
Page 61: e52 dental materials 26S (2010) e1-
show all

Abstracts of the Academy of Dental Materials Annual ... - IsiRed

You also want an ePaper? Increase the reach of your titles

Delete template?

Save as template?